Catheter Assembly Including Monitoring Capabilities

ABSTRACT

A catheter assembly or other elongate tubular device for use in establishing vascular or other access within the body of a patient is disclosed. The catheter assembly is equipped with one or more sensors that enable monitoring of one or more physiological aspects of the patient or physical aspect of the catheter assembly itself when the catheter assembly is disposed within the patient. Such aspects include central venous pressure, body temperature, ECG heart signals, oxygen levels, ultrasound data, glucose, etc. The catheter assembly includes the ability to wirelessly transmit or otherwise forward data relating to the detected physiological parameters to another location, such as a patient electronic medical record, smartphone or other mobile device, nurse station, etc. Catheter assemblies configured to detect the frequency of catheter flushing, flushing quality, etc., are also disclosed.

PRIORITY

This application is a continuation of U.S. patent application Ser. No.17/486,573, filed Sep. 27, 2021, which is a continuation of U.S. patentapplication Ser. No. 16/548,642, filed Aug. 22, 2019, now U.S. Pat. No.11,129,573, which is a division of U.S. patent application Ser. No.15/275,059, filed Sep. 23, 2016, now U.S. Pat. No. 10,433,790, whichclaims the benefit of U.S. Provisional Patent Application No.62/233,184, filed Sep. 25, 2015, and titled “Catheter Assembly IncludingMonitoring Capabilities,” each of which is incorporated herein byreference in its entirety.

BRIEF SUMMARY

Briefly summarized, embodiments of the present invention are directed toa catheter assembly or other elongate tubular device for use inestablishing vascular or other access within the body of a patient. Thecatheter assembly is equipped with one or more sensors that enablemonitoring of one or more physiological aspect or other parameter of thepatient, and/or physical aspects of the catheter assembly itself or itsoperation, when the catheter assembly is disposed within the patient.Such parameters include central venous pressure, body temperature, ECGheart signals, oxygen levels, ultrasound data, glucose, etc. Thecatheter assembly includes the ability to wirelessly transmit orotherwise forward data relating to the detected physiological/physicalaspects to another location, such as a patient electronic medicalrecord, smartphone or other mobile device, nurse station, etc. Catheterassemblies configured to detect the frequency of catheter flushing,flushing quality, etc., are also disclosed.

In one embodiment, therefore, a catheter assembly for insertion into abody of a patient is disclosed and comprises an elongate catheter tubedefining at least one lumen extending between a proximal end and adistal end, a bifurcation hub operably attached to the catheter tube,and an extension leg operably attached to the bifurcation hub, thebifurcation hub and extension leg defining at least one fluid passagewayin fluid communication with the at least one lumen of the catheter tube.At least one sensor is included with the catheter assembly, the at leastone sensor being configured to detect a physiological aspect of thepatient and/or physical aspect of the catheter assembly. A communicationmodule is also included and is configured to wirelessly transmit datasensed by the at least one sensor to a receipt location.

These and other features of embodiments of the present invention willbecome more fully apparent from the following description and appendedclaims, or may be learned by the practice of embodiments of theinvention as set forth hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of the present disclosure will be renderedby reference to specific embodiments thereof that are illustrated in theappended drawings. It is appreciated that these drawings depict onlytypical embodiments of the invention and are therefore not to beconsidered limiting of its scope. Example embodiments of the inventionwill be described and explained with additional specificity and detailthrough the use of the accompanying drawings in which:

FIG. 1 is a plan view of a catheter assembly in accordance with oneembodiment;

FIG. 2 is a plan view of a catheter assembly in accordance with oneembodiment;

FIG. 3 is a plan view of a catheter assembly in accordance with oneembodiment;

FIGS. 4A-4C are various views of a catheter securement device accordingto one embodiment;

FIGS. 5A-5C are various views of a catheter securement device accordingto one embodiment;

FIG. 6 is a perspective view of a catheter assembly in accordance withone embodiment;

FIG. 7 is a partial cross-sectional view of a catheter assembly inaccordance with one embodiment;

FIGS. 8A-8D are various views of an ultrasound signal graph;

FIGS. 9A and 9B are various views of a catheter assembly in accordancewith one embodiment;

FIG. 10 is a partial cross-sectional view of a hub of a catheterassembly according to one embodiment;

FIG. 11 is a view of a smartphone in accordance with one embodiment;

FIG. 12 is a perspective view of a catheter assembly and an auxiliarydevice in accordance with one embodiment;

FIG. 13 is a pressure graph for a catheter assembly;

FIG. 14 is a partial cross-sectional view of a pressure-sensing syringein accordance with one embodiment;

FIG. 15 is a partial cross-sectional view of a pressure-indicatingcatheter assembly according to one embodiment;

FIG. 16 is a view of a distal portion of a catheter assembly accordingto one embodiment;

FIG. 17 is a view of a distal portion of a catheter assembly accordingto one embodiment;

FIG. 18 is a perspective view of a distal portion of a catheter assemblyaccording to one embodiment;

FIG. 19 is a perspective view of a luer connector according to oneembodiment;

FIG. 20 is a perspective view of a luer connector of a catheter assemblyaccording to one embodiment;

FIG. 21 is a perspective view of a bifurcation hub of a catheterassembly according to one embodiment;

FIG. 22 is a simplified view of a pump system for use with a catheteraccording to one embodiment; and

FIG. 23 is a side view of a pump unit of the pump system shown in FIG.22 .

DETAILED DESCRIPTION

Reference will now be made to figures wherein like structures will beprovided with like reference designations. It is understood that thedrawings are diagrammatic and schematic representations of exemplaryembodiments of the present invention, and are neither limiting nornecessarily drawn to scale.

For clarity it is to be understood that the word “proximal” refers to adirection relatively closer to a clinician using the device to bedescribed herein, while the word “distal” refers to a directionrelatively further from the clinician. For example, the end of acatheter placed within the body of a patient is considered a distal endof the catheter, while the catheter end remaining outside the body is aproximal end of the catheter. Also, the words “including,” “has,” and“having,” as used herein, including the claims, shall have the samemeaning as the word “comprising.”

Embodiments of the present disclosure are generally directed to acatheter assembly or other elongate tubular device for use inestablishing vascular or other access within the body of a patient,together with associated components. Examples of such catheters includePICCs, central venous catheters, arterial catheters, Foley-type andurinary catheters, peripheral IVs, midline catheters, intermediate-dwellcatheters, feeding tubes, etc.

The catheter assembly or associated component is equipped with one ormore sensors that enable monitoring of one or more physiological aspector other parameters of the patient, and/or physical aspects of thecatheter assembly itself or its operation, when the catheter assembly isdisposed within the patient. Such aspects include central venouspressure, body temperature, ECG heart signals, oxygen levels, ultrasounddata, etc. The sensor(s) included with the catheter assembly are placedso as to enable detection of data related to these and/or otherparameters. In one embodiment, the one or more sensors are disposed inor proximate to a hub of the catheter assembly, though a variety ofother locations are also possible. Moreover, other components andstructures associated with the catheter assembly, such as a needlelessconnector for instance, can include one or more sensors for monitoringphysiological/physical aspects.

Further, the catheter assembly includes the ability to wirelesslytransmit or otherwise forward data relating to the detectedphysiological aspects/physical aspect to another location, also referredto herein as a receipt location. Examples of data receipt locationsinclude an patient electronic medical record (“EMR”), a patientmonitoring apparatus, a smartphone or other mobile device, a tablet, astorage location, a computer server, a nurse station, or a variety ofother destinations.

Reference is first made to FIG. 1 , which depicts various details of acatheter assembly (“catheter”), generally designated at 10, inaccordance with one embodiment. As shown, the catheter 10 includes anelongate catheter tube 12 defining one or more lumens 14 extendingbetween a proximal end 12A and a distal end 12B thereof. The proximalend 12A of the catheter tube is operably connected to a bifurcation hub(“hub”) 16, which in turn is operably connected to one or more extensionlegs 18. A connector 20, such as a luer connector, is disposed on aproximal end of the extension leg 18. The hub 16 includes two suturewings 22 that oppositely extend from the body of the hub 16. Each suturewing 22 includes a suture hole 24. Note that the hub 16 is also referredto herein as a “bifurcation hub” even in cases where only one fluidpassageway is defined therethrough.

In accordance with one embodiment, one or more sensors, also referred toherein as a “sensor array” 30, are included with the catheter 10 toenable the detection of date relating to one or more physiologicalaspects of the patient and/or physical aspects of the catheter when thecatheter tube 12 is disposed in the vasculature (as discussed here) orother suitable internal portion of the body of the patient. In thepresent embodiment, multiple sensors are included with the catheter 10,though the number, type, size, placement, function, and desired uses ofthe various sensors can vary from what is shown and described herein.Note that the sensor array 30 can, in one embodiment, include only onesensor. Note also that, where only one of a particular sensor isdiscussed below, it is appreciated that more than one of a particulartype of sensor can be included, in the same or different locationswithin the catheter assembly.

As shown in FIG. 1 , a pressure sensor 32 is included as part of thesensor array 30. In the present embodiment, the pressure sensor 32includes a central venous pressure (“CVP”) sensor and is disposed so asenable venous pressure of the patient to be sensed via the fluid (suchas blood and/or saline) typically present within the lumen 14 of thecatheter tube 12. As shown, in the present embodiment the pressuresensor 32 is disposed within the hub 16 so as to be in operablecommunication with a fluid passageway 26 within the hub that is in turnin fluid communication with the lumen 14 of the single-lumen cathetertube 12 shown in FIG. 1 . Other pressure sensor locations can alsoemployed, including within the catheter tube 12, the extension leg 18,etc. In one embodiment, the pressure sensor 32 is a medical pressuresensor NPC-100 or NPC-120, manufactured by Amphenol Corporation, thoughother pressure sensors may also be employed. In another embodiment, thepressure sensor includes a strain-sensitive Wheatstone bridge. Thesensing surface of the pressure sensor 32 in the present embodiment isin direct contact with fluid present in the fluid passageway of the hub16. Note that the size, shape, and other configuration of the hub 16 maybe increased from what is shown and described herein in order toaccommodate the sensor array 30, in one embodiment.

An ECG sensor 34, also referred to herein as an ECG electrode orelectrical sensor, is also included with the catheter assembly to enableECG signals emanating from the heart of the patient to be detected, inconjunction with an additional ECG sensor/electrode located on thepatient's skin or external portion of the catheter assembly/proximatethe catheter assembly, in one embodiment. As shown, in the presentembodiment the ECG sensor 34 is also disposed within the hub 16 so as tobe in direct contact with fluid present in the hub fluid passageway 26and the lumen 14 of the catheter tube 12. Other ECG sensor locations canalso be employed, including within the catheter tube 12, the extensionleg 18, etc. In the present embodiment, the ECG sensor 34 includes aconductive wire that is able to detect ECG signals of the patient heartthat are present in the fluid of the hub fluid passageway 26 andcatheter tube lumen 14, though other types of ECG sensors can beemployed. Further details regarding a system and method for using an ECGsensor for guiding the catheter assembly to a desired position withinthe body of a patient can be found in U.S. Pat. No. 8,849,382, entitled“Apparatus and Display Methods Relating to Intravascular Placement of aCatheter,” which is incorporated herein by reference in its entirety.

As described, the sensor array 30—including here the pressure sensor 30and the ECG sensor 34—is disposed within the hub 16, which is sized toprovide the needed volume for such sensors. Note that the size, shape,and configuration of the hub 16 can vary from what is shown anddescribed in order to house the sensor(s). In other embodiments, thesensors can be located in other portions of the catheter 10, includingalong or at either end of the catheter tube 12, the extension leg(s) 18,etc. Also note that a variety of sensors for detecting bodymeasurements, physiological aspects of the patient, and/or physicalaspects of the catheter can be included with the catheter assembly, someof which are discussed further below.

FIG. 1 further shows that the hub 16 (or other suitable location)includes a printed circuit board (“PCB”) 36 that is configured to governoperation of the sensor array 30, here including the pressure sensor 30and the ECG sensor 34. In one embodiment, the PCB 36 includes amicroprocessor for governing sensor operation. In one embodiment, thePCB 36 can further include a power source for powering the sensor array30, though in other embodiments the power source can be remotelydisposed from the PCB, and even the catheter 10. A non-volatile memorystorage location, such as flash memory for instance, can also beincluded on the PCB 36 to enable data sensed by the sensors of thesensor array 30 to be temporarily or permanently stored thereon. Thestorage location can be accessible by a user or can be transmitted to adesired location in a manner described below.

In the present embodiment, the PCB 36 further includes a transmissionmodule, such as a radio for enabling the PCB to transmit sensor datawirelessly to another receipt location, such as those referred tofurther above. Such wireless transmission can occur via Bluetooth,Wi-Fi, radiofrequency, near-field communication (“NFC”), GPS, ANT,ZigBee, or other manner utilizing electromagnetic radiation. In anotherembodiment, the sensor data can be transmitted from the catheter 10 viaa physical connection, such as via a removable physical connection,wires, etc. In another embodiment and as mentioned, sensor data, e.g.,central venous pressure, ECG signals, temperature, etc., are stored in amemory location included on the PCB 36, or other location on thecatheter 10. In yet another embodiment, the PCB 36 includes aclock/timer circuit.

In the present embodiment of FIG. 1 , the suture holes 24 of the suturewings 22 are configured to include electrical contacts to provide powerto the sensors 30 and 34 of the sensor array 30, as well as to the PCB36. In particular, an annular electrical contact 40 is included in eachsuture hole 24 of the bifurcation hub suture wings 22, with theelectrical contacts being operably connected to the PCB 36 and sensorarray 30. A securement device, such as the securement device 50 shown inFIGS. 4A-4C, is configured to be placed on the skin of the patient andoperably connect with and secure in place the catheter 10 once thedistal portion of the catheter has been inserted into the patient. Tothat end, the securement device 50 includes a retainer 54 mounted to anadhesive pad, and securement arms that are hinged so as to removablypivot atop the suture wings 22 of the bifurcation hub 16 (in a snap-fitarrangement) to secure the bifurcation hub in place.

In the present embodiment, the securement device 50 includes additionalfunctionality to provide power to the sensor array 30 and PCB 36. Indetail, the securement device 50 includes two posts 58, each of which isconfigured to serve as an electrical contact and each of which isoperably connected with a battery 62, also included in the securementdevice. The posts 58 are configured to be received within thecorresponding suture holes 24 of the catheter suture wings 22 such thatelectrical contact is established with the electrical contacts 40 of thesuture holes. The battery 62 included on the securement device 50 can,in this way, provide electrical power to the sensors 32, 34 and the PCB36 of the catheter hub 16. Of course, other external power sources canbe employed. In one embodiment, electrical contacts between the catheterand the securement device can also be utilized to transfer sensor datatherebetween. In another embodiment, the securement device can include aradio or other mode for transmitting sensor data received from thecatheter. In yet another embodiment, the PCB or a sensor can be includedon the securement device. It is appreciated that the size, shape, andother configuration of the securement device can vary from what is shownand described herein.

FIGS. 5A-5C depict details of the securement device 50 according toanother embodiment, wherein the securement device includes a pod 70 thatincludes a PCB and a battery for use with the sensor array 30 includedon the catheter 10, for instance. This eliminates the need for the PCBand/or battery to be disposed on the catheter 10 itself. FIGS. 5A and 5Cshow that the pod 70 includes the electrical contact 60 on an uppersurface of the retainer 54, where it is configured to electricallyconnect with a corresponding electrical contact on the hub 16 of thecatheter 10. Thus, when the hub 16 is removably retained by thesecurement arms 56 of the securement device 50, the sensor array 30 ispowered and governed by the battery and PCB of the pod 70. In oneembodiment, the pod 70 is configured to be removable from the securementdevice 50, thus enabling it to be reusable with successive securementdevices. This may be helpful when the catheter 10 and/or the securementdevice 50 are changed out. Thus, the pod 70—including the PCB, battery,and/or one or more sensors, etc.—can be removed from the securementdevice and placed in another, thus saving resources and cost. Note alsothat battery and PCB can be disposed in other locations as well. Theseand other variations are therefore contemplated. Further detailsregarding a catheter securement device related to those described hereincan be found in U.S. Pat. No. 6,770,055, entitled “Universal CatheterAnchoring System,” which is incorporated herein by reference in itsentirety.

Additionally, in one embodiment the securement device 50 can include anECG sensor (e.g., an electrode) that can cooperate with the ECG sensor34 of the catheter 10, thus enabling dual ECG signals to be detected andused to determine proximity of the distal end 12B of the catheter tube12 with respect to the heart. This configuration can also be used todetermine malposition of the catheter tube distal end 12B, both duringinitial catheter placement and subsequently during the indwelling of thecatheter within the patient. Sensor data from the pressure sensor 30 canalso be used in connection with the ECG signals to further detectcatheter tube distal end malpositions, in one embodiment.

FIGS. 2 and 3 show dual and triple-lumen catheter configurations,respectively, in contrast to the single-lumen configuration of FIG. 1 .As with that of FIG. 1 , the catheters 10 shown in FIGS. 2 and 3 eachinclude sensor arrays 30 similar to that shown in FIG. 1 , includingcorresponding pressure sensors 32, ECG sensors 34, and PCBs 36. Theelectrical contacts 40 for electrical connection with electricalcontacts 60 of the securement device 50 (FIGS. 4A-4C) are also shown.Note that each extension leg 18 of the catheters 10 in FIGS. 2 and 3includes a corresponding one of the pressure sensors 32 such thatpressure data may be sensed in each extension leg. In other embodiments,more or fewer sensors than what is shown here can be employed forsensing physiological aspects of the patient and/or physical aspects ofthe catheter assembly including, for instance, lactic acid sensors,oxygen sensors, ultrasound componentry, GPS location sensors,temperature sensors, sizing sensors to measure intraluminal diameter,fluid velocity sensors, glucose meters, oxygen sensors, lactic acidsensors, cardiac output sensors, accelerometers, blood volumetric andcardiac output sensors, etc.

FIG. 6 depicts the catheter 10 according to one embodiment, includingthree pressure sensors 30 in specified locations in the correspondingextension legs 18 and an ECG sensor 34 disposed in one extension leg,with each sensor operably connected to the PCB 36 disposed in the hub16. FIG. 5 thus demonstrates that the number, type, and placement of thesensor(s) and PCB can vary from what has already been shown anddescribed.

FIG. 7 depicts details of the sensor-equipped catheter 10 according toone embodiment, wherein the hub 16 includes an ultrasound assembly 80comprising upper and lower PCBs 82A and 82B configured to controlultrasound transducers 84A and 84B, respectively. The ultrasoundtransducers 84A and 84B can be used to ultrasonically evaluate the fluidpassageway, or lumen 92, of the bifurcation hub 16 to determine thecontents of the lumen, as shown in FIGS. 8A-8D. For instance, FIG. 8Ashows that when air is present in the lumen 92, no ultrasound signal ispresent, as depicted in an ultrasound signal graph 90 of FIG. 8A. Incontrast, when a fluid, such as fluid A, is present in the lumen 92, theultrasound transducers 84A and 84B return a signal of a specifiedvoltage consistent with the composition of fluid A, as seen by the graph90 of FIG. 8B. If a fluid B of differing composition from fluid A ispresent in the lumen 92, the ultrasound transducer 84A and 84B return asignal of specified voltage consistent with the composition of fluid B,as seen in the graph 90 of FIG. 8C. And when both fluid and air arepresent in the lumen 92, the graph 90 of FIG. 8D shows that a varyingvoltage signal is detected by the ultrasound transducers 84A and 84B. Inthis way, the ultrasound transducers 84A and 84B, coupled with thebattery and PCB as discussed further above, can assist the user indetermining the presence of particular substances in the lumen 92 of thehub 16, or the lumens of other catheter components, depending onplacement of the ultrasound transducers. In another embodiment, only asingle ultrasound transducer is employed.

FIGS. 9A and 9B depict details of the sensor-equipped catheter 10according to another embodiment, wherein the hub 16 includes a PCB 82disposed therein and operably connected to a temperature sensor 100,such as a thermocouple in one embodiment, positioned so as to measurecore body temperature via blood or other fluids present in the lumen 14of the catheter. As FIG. 9B shows, the temperature sensor 100 can beplaced in proximity to the lumen 14 via a skiving or cavity 108longitudinally defined in the catheter tube 12 and/or hub 16. Potting106 can be used to fill the cavity 108 about the temperature sensor 100.In one embodiment, the temperature sensor 100 includes a series 400Model 401 thermistor available from Cole-Palmer Inc., Vernon Hills, IL.

FIG. 10 shows that, in one embodiment, a variety of sensors can beincluded as part of the sensor array 30 within the hub 16 or othersuitable location. As depicted in FIG. 10 , in one embodiment the hub 16includes disposed therein the pressure sensor 32, the PCB 36 (includinga processor 36A and a wireless communication module 36B), upper andlower ultrasound transducers 84A and 84B, a temperature sensor 100, andan oxygen sensor 110. The various sensors are arranged as needed inproximity to the fluid passageway 26 of the hub 16 so as to sense therelevant parameters as detected in the fluid present in the fluidpassageway. The particular arrangement of the sensors can vary from whatis shown here.

FIG. 11 shows that, in one embodiment a smartphone 100 can be thereceipt location for wirelessly receiving data from one or more of thesensors of the sensor array, as discussed in the embodiments above.Examples of wireless modes by which the data can be transmitted includeBluetooth, Wi-Fi, radiofrequency, near-field communication (NFC), ANT,ZigBee, etc. Such data transmission can be relayed through asoftware-based application or other intermediary device. This enables aclinician to receive mobile updates and other sensor data 124 from thecatheter 10 via a display 122 of the smartphone 120 (or by other mediumsincluding sound, vibration, etc.) in order to be able to monitor theprogress or condition of the patient. Other locations for receipt of thesensor data as described above include a patient electronic medicalrecord (“EPR”), a patient monitoring apparatus, other mobile devicesincluding electronic tablets and laptop computers, an electronic storagelocation, a computer server, a nurse station, medical equipment such asa pump attached to the catheter, and a variety of other destinations. Itis appreciated that devices, components, computers, etc. that arelocated at the receipt location can perform operations on the receiveddata, including analysis, trending, alarm functions, etc.

FIG. 12 depicts the catheter 10 according to another embodiment, whereinthe catheter is shown inserted into an arm 128 of the patient such thata majority portion of the catheter tube 12 is disposed within thevasculature of the patient. The hub 16, including one or more sensors,is also shown operably connected to an auxiliary device, such as anarmband 130, placed around the patient arm 128 via a connecting wire134. The armband 130 is placed in proximity to the external portion ofthe catheter 10 in the present embodiment, though its location andparticular shape, size, configuration, and body attachment scheme canvary in other embodiments. As shown, the armband 130 includes variouscomponents to work in concert with the sensor(s) of the catheter 10 viathe connection wire 134, including the PCB 36 and a wirelesscommunication module 136 (which in other embodiments is included withthe PCB). Sensor data detected by the sensor(s) of the catheter 10 canbe forwarded from the catheter 10 to the components of the armband 130via the connecting wire 134, where the data can be processed (e.g., bythe PCB 36) and/or transmitted to a remote location (e.g., by thewireless communication module 136). In another embodiment, the operableconnection between the catheter 10 and the armband 130 is a wirelessconnection as well.

Placement of the PCB 36 and the wireless communication module 136 on thearmband 130 frees up space on the catheter and may prevent the need forreplacing relatively expensive components when the catheter 10 itself isperiodically replaced with a new catheter. In such a case, the armband130 can be simply connected to the new catheter, and the PCB 36 andwireless communication module 136 can begin to function with the newcatheter as they did with the previous catheter. Note that various othercomponents can also be included on the armband 130, including a batteryfor powering the sensor(s) included on the catheter, additional sensorsincluding an ECG sensor, etc. As mentioned, the armband 130 isrepresentative of other wearable and non-wearable auxiliary devices thatcan be operably connected to the sensor(s) of the catheter 10 in orderto facilitate their operation. Also note that the components included onthe armband/auxiliary device can be replaceable/reusable, in oneembodiment. In one embodiment, the PCB, battery, and/or wirelesscommunication module can be included on the catheter securement device.In another embodiment, the above-described components can be included ona platform that is removably attachable to the armband. In anotherembodiment, the armband or similar component includes a disposableshield to isolate it from the patient and/or to provide isolation fromcontaminants.

Several of the above-described embodiments include the pressure sensor32 that is configured to sense data relating to the central venouspressure of the patient in which the catheter 10 is disposed. In anotherembodiment, data sensed by the pressure sensor 32 can be furtheremployed to detect when an occlusion, such as a fibrin sheath orthrombus, may be present in the lumen 14 of the catheter tube 12. FIG.13 shows a pressure graph 140 including a pressure curve 142 thatdepicts the level of pressure over time in the catheter tube lumen 14 assensed by the pressure sensor 32, such as in the pressure sensorconfiguration of FIG. 10 , for instance, during a flushing procedurewherein fluid is flushed through the catheter 10 by a user using asyringe connected to the luer connector 20 in order to maintain patencyof the catheter tube lumen 14. As shown, the pressure curve 142 includesvarious pressure peaks 144 that are caused by the user pulsing thesyringe with moments of additional pressure. This is performed so as toclear any minor obstructions that may have formed within the cathetertube lumen 14 or in other areas of the catheter fluid path. When anocclusion is present at the distal end 12B of the catheter tube and/orwithin the lumen 14 (see occlusion 178 in FIG. 15 for example), thepressure curve 142 will be elevated (i.e., shifted vertically upwardalong the pressure y-axis) or widened (i.e., lengthened along the timex-axis).

In more detail, hydraulic resistance R of a fluid is generally relatedto the fluid flow rate Q and infusion pressure P by the relationship:

P=Q*R,  (1)

which yields:

R=t1∫t2P dt/V,  (2)

where V is a known volume of fluid to be infused into the catheter 10,t1 is the time at the beginning of a fluid infusion process, t2 is thetime at the end of the fluid infusion process (referring to FIG. 13 ),noting that P indicates the instantaneous pressure during each moment ofthe fluid infusion procedure. Comparing the resistance R of the fluidinfusion through the catheter tube 12 for a certain period of time(using the above equations) and comparing it with the resistance R₀ at aprevious time, such as when the catheter 10 was first inserted into thepatient and was considered un-occluded, or patent, can yield thepercentage of possible occlusion in the catheter tube according to:

% occlusion=R/R ₀  (3)

Detection of an elevated pressure within the catheter fluid path by thepressure sensor 32, such as via the above-described calculations, canalert the user to a possible occlusion such that corrective measures canbe taken. Further, data storage in a memory location located on thecatheter 10 with the PCB 36 or remotely located in a patient electronicmedical record (or other remote storage location) can be employed tomeasure the catheter flushing pressure over time so as to detectpressure changes over time. This data comparison over time can beperformed for any one of the sensors located on the catheter 10, as maybe appreciated. Of course, the data sensed by the sensors and stored ina memory location can be used for a variety of other uses as well,including historical trends, etc . . . .

FIG. 14 depicts various details of a pressure—sensing syringe 150according to one embodiment, including a housing 152 that defines acavity 154 with a distal end fluid outlet 156. A plunger 158 is disposedwithin the cavity 154 and is attached to a spring 160, initiallydisposed in a compressed state and releasable by a release button 162disposed on a proximal end of the syringe 150. A known quantity of 0.9%normal saline 164 or other suitable liquid is disposed in the cavitydistal to the plunger 158 such that the saline exits the fluid outlet156 when the spring 160 is actuated by the release button 162. Thesaline 164 ejected by the syringe 150 is injected into the extension leg18—then through the hub 16 and lumen 14 of the catheter tube—when thesyringe is operably attached to the corresponding luer connector 20.

A pressure sensor 166 is included at the fluid outlet 166 to measure thepressure of the known quantity of saline 164 as it exits the fluidoutlet 156 and enters the catheter 10 to which the syringe 150 isconnected. A processor unit 170 and a display/control unit 172 areincluded to measure and calculate (such as via the equations describedfurther above) the pressure present as the saline 164 is ejected by theplunger 158 through the fluid outlet. Further calculations can beperformed by the processor unit 170 to determine the hydraulicresistance of the injection, thus yielding the amount of occlusionpresent in the fluid path of the catheter 10, using the known volume ofinjected saline 164, the injection pressure as measured by the pressuresensor 166, and the amount of time needed for injection of all thesaline to occur. In one embodiment, the user can input the size of thecatheter tube lumen 14 and the length thereof via the display/controlunit 172.

The results describing the amount of any occlusion present in thecatheter fluid path (such as in % of fluid path occluded, for instance)can be depicted on the display/control unit 172 or wirelesslytransmitted to a receipt location via a wireless communication moduleincluded with the processor unit 170, for instance. Corrective measuredcan then be taken by the user, if needed.

Note that historical pressure/occlusion data can be stored by a memorylocation of the processor unit 170, for instance, for call-up anddepiction by the display/control unit 172, in one embodiment. In oneembodiment, the plunger 158 of the syringe 150 is manually depressibleby the user, thus obviating the need for the spring 160, or can be apressurized gas source to push the plunger, etc. The location of thepressure sensor 166 can also vary from what is shown and describedherein.

Note that, in another embodiment, the pressure sensor 32 can be used todetermine when the catheter tub 12 has been malpositioned within thevasculature by sensing pressure differences between expected values fora proper placement and actual sensed values as detected by the pressuresensor. When this situation occurs, proper steps to correct themalposition can be taken. In another embodiment, the pressure sensor 32and the electrical (ECG) sensor 34 can work in concert to detectcatheter malposition based on venous pressure readings and ECG signalanalysis.

FIG. 15 depicts various details of the catheter 10 that includes theability to detect occlusions, such as a partial occlusion 178 shown atthe distal end 12B of the catheter tube 12, according to one embodiment.As shown, the catheter 10 includes a pressure detection module 180operably attached to the luer connector 20 of the catheter 10. A syringe182 is attached to a proximal end of the pressure detection module 180so as to provide an injection of saline or other suitable fluid througha flow lumen 184 of the pressure detection module 182 and into theextension leg 18 to flow through the catheter 10.

As shown, the pressure detection module 180 includes a pressureindicator 188 in fluid communication with the flow lumen 184. Thepressure indicator 188 is configured to extend an indicator pieceoutward when a predetermined pressure is encountered in the flow lumen184 of the pressure detection module. As such, when a fluid pressure inexcess of the predetermined pressure is encountered in the catheterlumen 14 during fluid injection into the system by the syringe 182 (orother suitable fluid injection device), the pressure buildup extendsproximally through the hub 16, extension leg 18, and flow lumen 184,causing the indicator piece of the pressure indicator to extend outward,thus indicating to the user that an occlusion may be present. It isappreciated that indicator pieces of differing configurations can beemployed. In the present embodiment, the pressure detection module 180is a separate component attachable to the catheter 10; in otherembodiments the pressure detection module is integrally formed with thecatheter.

FIG. 16 depicts possible locations for sensors of the sensor array 30 inthe catheter tube 12. As shown, various sensors 200 of the sensor array30 are disposed proximate the distal end 12B of the catheter tube 12,together with the pressure sensor 32 disposed proximally to the othersensors. FIG. 16 further shows that a connection wire 192 extends alonga central portion of the catheter tube, e.g., within a septum separatingthe lumens 14 from one another, to power the sensors 200 of the sensorarray 30. In another embodiment, the connection wire 192 can be disposedin a dedicated lumen extending the length of the catheter tube. Notethat placement of the sensor(s) a distance proximal to the catheter tubedistal end 12B, such as the pressure sensor 32 here, enables thecatheter tube 12 to be distally trimmable.

FIG. 17 depicts another configuration for including a sensor 200 in thecatheter tube 12, wherein the sensor 200 is disposed in the wall of thecatheter tube 12 within a skive cut 198 longitudinally defined in thewall. Potting 204, such as a thermally conductive epoxy, polyurethane,or RTV potting, is included to cover the sensor 200. In one embodiment,the sensor 200 includes a glucose sensor for sensing blood glucoselevels and is not potted such that the glucose sensor has direct contactwith the blood. These and other possible sensor locations are thereforecontemplated.

FIG. 18 depicts another configuration for including a sensor in thecatheter tube 12, wherein the sensor 200 is disposed on an inner surfaceof one of the lumens 14 of the catheter tube 12 proximate the distal end12B thereof. Potting 204 can be included to insulate and cover thesensor 200 as needed. In one embodiment, the potting 200 protects thesensor 200 from exposure to liquids while enabling heat to betransmitted therethrough. FIG. 18 further shows that wire-basedelectrodes 210 can be disposed in the wall of the catheter tube 12proximate the distal end 12B of the catheter tube 12 so as to be exposedon an outer surface thereof. The sensors 210 can be formed asconcentrically disposed sensors that can be employed to make volumetricmeasurements to determine the size of the vessel in which the cathetertube is disposed, thus assisting the user in determining a possiblemalposition of the catheter tube in an undesired vessel. These and otherpossible sensor configurations are therefore contemplated.

FIG. 19 depicts various details of a flush sensor 222 for detecting whenthe desired periodic flushing of the catheter 10 with a fluid hasoccurred, also referred to herein as a flush state of the catheter tube12. As shown, the flush sensor 222 is disposed within a cavity 220 ofthe luer connector of the catheter extension leg 18, though otherlocations can be employed for the sensor. The flush sensor 222, alsoreferred to herein as a detection module, includes a lever 224 biased toan extended position by a spring 226, as shown. The flush sensor 222 isoperably connected to a processor of a PCB (such as the PCB 36 shown inFIG. 10 ) or other suitable component (disposed within the luerconnector 20, for instance) to govern its operation and process itssensed data.

In operation, when a syringe or other component is inserted into thecavity 220 of the luer connector 20 to flush the catheter 10 with salineor other suitable fluid, the lever 224 of the flush sensor 222 isdepressed, which causes a signal to be sent to the processor indicatingthat a flushing procedure is occurring. The time of flushing or otherdata relating to the flushing procedure can be noted, stored or used bythe processor, or wirelessly transmitted to a receipt location in amanner similar to that discussed further above. In one embodiment, theflush sensor 222 and the processor of the PCB 36 are referred to as aflush sensor assembly, though it is appreciated that the assembly caninclude additional components. In another embodiment, an electricalsensor can be employed as the flush sensor, wherein the electricalsensor includes a circuit that is broken each time a component isinserted into the connector 20. Breaking of the circuit can reset atimer circuit to measure the next period until the flush sensor is againactivated.

In one embodiment, for instance, it is desired that the catheter 10 beflushed at least once every 12 hours. When the flush sensor 222 detectsa flushing procedure as described above, a timer circuit in theprocessor is re-set to begin counting time to measure the next timeperiod until the flush sensor 222 is again depressed to indicate a newflushing procedure.

FIG. 20 shows that a light array 230, such as a collection of a red LEDlight, yellow LED light, and green LED light, can be included on asurface of the luer connector 20 to visually indicate the flushingstatus of the catheter 10, in one embodiment: a green light indicatesless than 10 hours have elapsed since the last flushing procedure wasdetected; a yellow light indicates more than 10 hours but less than 12hours have elapsed since the last flushing procedure; a red lightindicates that more than 12 hours have elapsed since the last flushingprocedure. The processor governs the operation of the light array and itis understood that the lights can vary in number size, location,purpose, indicated elapsed time, etc. Further, it is appreciated thatother types of sensors, including sensors that detect the presence ofliquid within the luer connector cavity 220, can also be employed todetect flushing procedures.

In another embodiment, the light array 230 can be used as follows: thegreen light flashes after an acceptable flushing procedure has beenperformed; the red light blinks after a non-acceptable or incompleteflushing procedure has occurred; the yellow light blinks or is turned onto indicate a possible occlusion present in the catheter tube 12. In yetanother embodiment, the yellow light (or other light) can be lit toserve as a reminder to flush the catheter10.

It is appreciated that in another embodiment the luer connector 20 orother portion of the catheter 10 can include a push button (or otheruser-activated component) that can be depressed at the time of catheterflushing, thus re-setting the timer circuit. In this case, a countingcircuit can also be included to count the number of times the connector20 or other component is accessed.

FIG. 21 shows that the light array 230 can be disposed in otherlocations on the catheter 10, including in this embodiment disposal onthe hub 16. These and other possible locations, such as the cathetertube or extension legs, or the armband 130 of FIG. 12 for example, aretherefore contemplated. In other embodiments, the light array can beemployed to alert the user to other sensed conditions, includingelevated body temperature/fever, onset of sepsis (see further below),catheter occlusion, low blood oxygen levels, etc. Further, other indiciacan be employed, in addition to lights, to alert the user with respectto the sensor data, including sound, vibration, etc. either on thecatheter itself or at the remote receipt location to where the data iswirelessly transmitted.

Note that the flush sensor 222 can be included in other areas as well,including a needleless connector that is configured to operably attachto the luer connector, for instance.

In one embodiment, the pressure sensor 32 can be used—alone or inconcert with the flush sensor 222 described above—to detect and/orcharacterize flushing procedures. For instance, in one embodiment theflush sensor 222 can be used to detect a flushing procedure, while thepressure sensor 32 can sense the amount of pressure present during theflushing procedure, thus detecting possible occlusions. Indeed, in oneembodiment, the pressure sensor 32 can be used to determine flushingfrequency of the catheter 10, flushing technique, flushing time, numberof times of catheter access, time expired since last catheter access,etc., by measuring pressure within the lumen 14 of the catheter as afunction of time, using timer circuitry included on the PCB 36, forinstance. Such sensor data can be stored by a memory location located onthe PCB 36, for instance, or transmitted to another local or remotereceipt location, as has been described. Processing to determine suchmonitoring can be performed by a processor included on the PCB 36 orremotely.

In one embodiment, sensor data from catheter sensors, such as thepressure sensor 32 and a core body temperature sensor, can be employedto detect patient conditions, such as sepsis. In particular, respiratoryrate, heart rate, and body temperature can be sensed via the pressuresensor 32 and the core body temperature sensor 100 included with thecatheter 10, such as in the configuration shown in FIG. 10 . These threeparameters comprise three of four parameters that are typically employedto determine the onset of sepsis. As such, monitoring of theseparameters via the catheter 10 as described herein can be used toprevent detect and ameliorate complications from sepsis, in oneembodiment.

FIG. 22 depicts a sensor-based catheter assembly according to anotherembodiment. In detail, the catheter 10 is shown with its catheter tube12 disposed within the vasculature of the patient and the two luerconnectors 20 operably connected to supply lines 240 configured to bothprovide fluid to and remove fluid from the lumens of the catheter. Apump unit 250 is included to enable fluid movement through the supplylines 240. A saline fluid drip assembly 252 is also included to providefluid to the pump unit for movement through the supply lines, if neededor desired. A syringe, such as the syringe 182, is included to providean additional fluid inlet in a corresponding one of the supply lines240.

FIG. 23 depicts further details of the pump unit 250 of FIG. 22 ,including a fluid inlet 256A and a fluid outlet 256B that are configuredto operably connect with the corresponding supply lines 240 (FIG. 22 )to bring blood or other fluid from within the patient vasculature viathe catheter 10 (through the fluid inlet 256A) to the pump unit 250 andto return the fluid to the patient vasculature (through the fluid outlet256B) via the catheter. A pump 258 is included in the pump unit 250 tocause the movement of the fluid. Additionally, various input ports 260are included on the pump unit 250 in fluid communication with the fluidinlet 256A to enable additional fluids to be input, including heparin,saline, arterial input, etc.

One or more sensors 200 are also included in the pump unit 250 andarranged so as to measure one or more physiological aspects of thepatient blood. Examples of such sensors include a glucose meter, oxygensensor, lactic acid sensor, cardiac output sensor, etc. The location ofthe sensors 200 can vary from what is shown here. Disposal of thesensors 200 in the pump unit 250 as opposed to the on the catheter 10itself enables sensors of relatively greater size to be employed withoutunduly increasing the size of the catheter.

Embodiments of the invention may be embodied in other specific formswithout departing from the spirit of the present disclosure. Thedescribed embodiments are to be considered in all respects only asillustrative, not restrictive. The scope of the embodiments is,therefore, indicated by the appended claims rather than by the foregoingdescription. All changes that come within the meaning and range ofequivalency of the claims are to be embraced within their scope.

What is claimed is:
 1. A method of making a catheter assembly,comprising: producing a catheter having a proximal end and a distal end,the proximal end configured to be positioned outside of a body of apatient when the catheter is in use, the distal end configured to bepositioned inside of the body of the patient when the catheter is inuse; integrating a flush sensor in the proximal end of the catheter, theflush sensor configured to detect when the catheter assembly is beingflushed with fluid; coupling a pressure sensor to the catheter, thepressure sensor configured to operate with the flush sensor to detectwhen the catheter assembly is being flushed with fluid; and providing anauxiliary device separated from the catheter, the auxiliary deviceoperably attached to the flush sensor and the pressure sensor, theauxiliary device configured to relay information from the flush sensorand the pressure sensor to a receipt location.
 2. The method accordingto claim 1, wherein the flush sensor is configured to be activated whena component is operably connected to the catheter assembly.
 3. Themethod according to claim 2, wherein the flush sensor includes a leverthat is configured to be displaced when the component is operablyconnected to the catheter assembly.
 4. The method according to claim 3,wherein integrating the flush sensor comprises including the flushsensor in at least one of a luer connector and a needleless connectorincluded with the catheter assembly.
 5. The method according to claim 1,wherein the auxiliary device comprises a wireless communication moduleconfigured to wirelessly transmit the information to the receiptlocation.
 6. The method according to claim 5, wherein the wirelesscommunication module is configured to transmit the data via at least oneof Bluetooth, Wi-Fi, near-field communication, and radiofrequencysignals.
 7. The method according to claim 5, further comprisingincorporating the auxiliary device into a securement device, wherein thewireless communication module is included on a printed circuit board inthe securement device.
 8. The method according to claim 5, wherein theauxiliary device is configured to be worn on the body or clothing of thepatient.
 9. The method according to claim 5, wherein the auxiliarydevice comprises an armband.
 10. The method according to claim 1,wherein the auxiliary device includes a printed circuit board and abattery, the printed circuit board and the battery operably connected toat least one of the flush sensor and the pressure sensor via aconnecting wire.
 11. The method according to claim 1, wherein thereceipt location is selected from the group consisting of a smartphone,a storage device, a patient electronic medical record, a mobile device,a computer server, a laptop computer, a nurse station, and a printer.12. The method according to claim 1, further comprising incorporating atleast one additional sensor into the catheter assembly, wherein the atleast one additional sensor is selected from the group consisting of atemperature sensor, an ultrasound transducer, an electrical sensorconfigured to detect ECG signals, and a glucose sensor.
 13. The methodaccording to claim 1, wherein the catheter includes a catheter hub atthe proximal end, further comprising incorporating an oxygen sensor inthe catheter hub.
 14. The method according to claim 13, furthercomprising incorporating a catheter physical aspect sensor into thecatheter assembly.
 15. The method according to claim 1, furthercomprising including at least one light on the catheter assembly, thelight configured to operate in conjunction with one or both of the flushsensor and the pressure sensor.
 16. The method according to claim 1,further comprising incorporating a light array coupled to a timingcircuit into the catheter assembly, the light array configured tovisually indicate a status of the catheter.
 17. The method according toclaim 1, further comprising including a temperature sensor in thecatheter assembly, the pressure sensor and the temperature sensorconfigured to sense a respiratory rate, a heart rate, and a bodytemperature of the patient in order to determine whether a sepsiscondition is present.
 18. The method according to claim 17, wherein thepressure sensor and the temperature sensor are disposed in a catheterhub positioned at the proximal end of the catheter.
 19. The methodaccording to claim 18, wherein the temperature sensor extends in alongitudinal cavity in a wall of the catheter, and wherein thelongitudinal cavity is filled with potting around the temperaturesensor.
 20. The method according to claim 1, further comprisingproviding a pressure detection module detachably connectable to thecatheter, wherein the pressure detection module comprises a pressureindicator in fluid communication with a lumen of the pressure detectionmodule, the lumen of the pressure detection module in fluidcommunication with the lumen of the catheter.
 21. The method accordingto claim 20, wherein the pressure indicator includes an indicator piecethat activates upon detection of a fluid pressure in excess of apredetermined pressure in the lumen of the catheter.